As space-time inflated in the seconds after the Big Bang, it's possible that 'bubbles formed,' creating new universes.
The first direct evidence of cosmic inflation — a period of rapid expansion that occurred a fraction of a second after the Big Bang — also supports the idea that our universe is just one of many out there, some researchers say.
On Monday, March 17, scientists announced new findings that mark the first-ever direct evidence of primordial gravitational waves — ripples in space-time created just after the universe began. If the results are confirmed, they would provide smoking-gun evidence that space-time expanded at many times the speed of light just after the Big Bang 13.8 billion years ago.
The new research also lends credence to the idea of a multiverse. This theory posits that, when the universe grew exponentially in the first tiny fraction of a second after the Big Bang, some parts of space-time expanded more quickly than others. This could have created "bubbles" of space-time that then developed into other universes. The known universe has its own laws of physics, while other universes could have different laws, according to the multiverse concept. [Cosmic Inflation and Gravitational Waves: Complete Coverage]
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